Urban Air Mobility Fleet Manager Gap Analysis and System Design

NASA's Urban Air Mobility (UAM) Sub-Project is engaged in research to support the introduction of air taxis into the National Airspace System. Such operations will require a range of communication, navigation, and surveillance systems. Air vehicles for UAM are under development and will initially have human pilots. Separation from other aircraft, obstacles, and weather may be a pilot responsibility or provided by an operator's ground-based systems. Eventually, air taxis may be flown from the ground or fly autonomously. There will be a need for dispatch services for UAM. This report presents a gap analysis, data and capability requirements, and workstation design concepts for the UAM dispatcher or Fleet Manager (FM) position

Validity of IPhone Apps to Measure Knee Range of Motion in Clinical Settings

poster abstractRange of motion (ROM) of joints is a measure of musculoskeletal function in clinical and athletics settings. ROM in uniaxial joints is measured using a two-arm goniometer (GON). Although GON are inexpensive and can be used in different planes, there are limitation in accuracy and reproducibility. New IPhone apps have been developed to measure ROM using photography (PT tools, Dr.Goniometer and Photogoniometer), or the accelerometry and they also provide a permanent record of the measurement. The purpose of this study to compare the accuracy of the several IPhone apps against standard clinical [goniometer (GON)] and laboratory [electro-goniometer (EGON)] methods of measuring ROM. An EGON was attached the knee of 15 subjects knee while the performed five trials of knee extensionflexion). Three photography and one accelerometer based apps were compared against the EGON. The EGON data were compared against the GON used in clinical settings. Intraclass correlation (ICC) between methods and the Bland-Altman method (BAM) of assessing clinical agreement were used to determine validity. The ICC between the EGON and GON was r =.969 and with a BAM showing good clinical agreement between the two techniques. ICC of the photography based apps ranged from (.709-.721) and the accelerometer based goniometer was .671. The results of the BAM showed moderate to poor agreement between the methods, which indicate the some of the apps may not be suitable to use in clinical settings. The small screen size of the IPhone makes it difficult to accurately identify the joints centers. Small errors on placing the joint centers can lead to large errors of the knee joint angle. Accelerometer based apps are difficult to align and can be affected by muscle and adipose tissue of leg. It is possible that photography based apps when used on an IPad will provide better accuracy and be suitable to clinical settings

Cation Effects in p-Type Dye-Sensitized Solar Cells

The performance of dye sensitized solar cells depends on the properties and interactions of three fundamental components: the semiconductor, chromophore, and electrolyte. Performance dependence on electrolyte cation species has not been well studied in p-type systems. The effects of these species in n-type systems are significant, producing large shifts in semiconductor flat band potential, charge transfer kinetics, and open circuit voltage. Modifying the spectator cation has been shown to increase open circuit voltage by over 50% in two common electrolyte systems. A champion open circuit voltage of 351 mV has been achieved, representing a record for the chromophore employed. Our results indicate that applying this knowledge to any p-type dye sensitized solar cell system can yield improvements in important device metrics.Bachelor of Scienc

Doubly Robust Kernel Statistics for Testing Distributional Treatment Effects Even Under One Sided Overlap

As causal inference becomes more widespread the importance of having good tools to test for causal effects increases. In this work we focus on the problem of testing for causal effects that manifest in a difference in distribution for treatment and control. We build on work applying kernel methods to causality, considering the previously introduced Counterfactual Mean Embedding framework (\textsc{CfME}). We improve on this by proposing the \emph{Doubly Robust Counterfactual Mean Embedding} (\textsc{DR-CfME}), which has better theoretical properties than its predecessor by leveraging semiparametric theory. This leads us to propose new kernel based test statistics for distributional effects which are based upon doubly robust estimators of treatment effects. We propose two test statistics, one which is a direct improvement on previous work and one which can be applied even when the support of the treatment arm is a subset of that of the control arm. We demonstrate the validity of our methods on simulated and real-world data, as well as giving an application in off-policy evaluation.Comment: 9 pages, Preprin

UAM Fleet Manager Gap Analysis

NASA's Urban Air Mobility (UAM) Sub-Project is engaged in research to support the introduction of air taxis into the National Airspace System. Such operations will require arrange of communication, navigation, and surveillance systems. Air vehicles for UAM are under development and will initially have human pilots. Separation from other aircraft, obstacles, and weather may be a pilot responsibility or provided by an operator's ground-based systems. Eventually, air taxis may be flown from the ground or fly autonomously. There will be a need for dispatch services for UAM. This report presents a gap analysis, data and capability requirements, and workstation design concepts for the UAM dispatcher or Fleet Manager (FM) position. This presentation reviews the gap analysis report and outlines user interface design

UC-257 GTRI: Analysis of Alternatives

The Capstone project Analysis of Alternatives focuses on research and testing workstation deployment software and see if they can fulfill certain requirements that GTRI has requested. Planning and research was first conducted on ten different software that are available on the market where each software was evaluated on a point based system based on the requirements given to us by the company. After researching the ten software three are chosen that best fit the requirements from the company and are then moved to the testing phase. After testing the three chosen software the team will collectively decide which one to recommend to the company with a detailed analysis

Adoption of site-specific variable rate sprinkler irrigation systems

More than 20 years of private and public research on site-specific variable rate sprinkler irrigation (SS-VRI) technology on self-propelled center pivot and linear move irrigation systems has resulted in limited commercial adoption of the technology. Competing patents, liability, and proprietary software have affected industry’s willingness to move into a new technology area. Documented and proven water conservation strategies using site specific irrigation are quite limited. Marginal costs associated with site-specific technologies are high. Although sales of SS-VRI are increasing, they are primarily being used for eliminating irrigation and chemigation on non-cropped areas of a field or for land application of liquid agricultural and municipal wastes. Various aspects of SS-VRI technologies for general crop production are beginning to slowly gain widespread acceptance; however, their uses are largely focused on addressing symptoms of poor design and suboptimal water and nutrient management. Although currently underutilized, SS-VRI technology has the potential to positively impact crop water productivity, water and energy conservation, and the environment. There are also few economic incentives to motivate growers to move to higher levels of SS-VRI management. Greater adoption rates will likely require higher costs for water and energy, severely restricted water diversions on a broad scale, and enforcement of compliance with environmental and other regulations. Sustainable use of SS-VRI will require strong research support, which is currently limited. In the short term, adoption of SS-VRI technologies will be enhanced by addressing equipment deficiencies and research developing basic criteria and systems for defining management zones and locations of various sensor systems for both arid and humid regions. Training adequate personnel to help write site-specific variable rate irrigation prescriptions in humid and arid areas to assist growers with the decision-making process is also a high priority. There is also a large need to educate government boards and bankers on the potential benefits of these systems. The long-term challenges will be to demonstrate that SS-VRI will improve water management or increase net returns. There is a critical need to develop fully integrated management systems with supporting elements that accurately and inexpensively define dynamic management zones, sense within-field variability in real time, and then adaptively control site-specific variable rate water applications, which will be challenging as significant knowledge gaps exist

Wafer-scale magnesium diboride thin films and devices with tunable high kinetic inductance

Progress in superconducting device and detector technologies over the past decade have realized practical applications in quantum computers, detectors for far-IR telescopes, and optical communications. Superconducting thin film materials, however, have remained largely unchanged, with aluminum still being the material of choice for superconducting qubits, and Nb compounds for higher frequency devices. $\mathrm{MgB}_2$, known for its highest $\mathrm{T}_c$ (39 K) among metallic superconductors, is a viable material for higher frequency superconducting devices moving towards THz frequencies. However, difficulty in synthesizing thin films have prevented implementation of $\mathrm{MgB}_2$ devices into the application base of superconducting electronics, despite promising preliminary results for a number of applications. We have developed smooth and uniform $\mathrm{MgB}_2$ films on 4-inch Si wafers by depositing uniform Mg-B co-sputtered film, capping the film in situ to create a closed environment, followed by an optimized post-annealing step. We further report mature device fabrication processes and demonstrate test structures to measure properties of the films. This includes resonators with internal Q factor over $\mathrm{10}^4$ at 4.5 K and tunable high kinetic inductance (5-50 pH/$\square$ readily achieved in a 40 nm film), opening up the path for development of high frequency and high temperature $\mathrm{MgB}_2$ microdevices